ChRoMicro - Cheap Robotic Microhelicopter HOWTO (EN)
RC model helicopter prices have reached a point where all sorts of challenging (i.e. crash-prone) robotics projects become affordable. This document explains how to build a 300 g helicopter with...
View ArticleCFcam - Connecting a CMOS camera to a Gumstix Connex motherboard
This document explains how to connect a digital CMOS image sensor directly to the CompactFlash port of a Gumstix Connex computer (or similar PXA255-based platform).
View ArticlepxaRC - R/C and robotics software for Linux/PXA255/PXA270
pxaRC is a collection of drivers and utilities for remote-control and robotics applications on Linux/PXA255/PXA270-based platforms such as the Gumstix basix, connex and verdex motherboards.
View ArticleHome server form factor for 600x300 mm ETSI racks
I argue that manufacturers of home servers and NAS appliances should standardize on the half-depth ETSI subrack form-factor and cabling conventions: 19" mounting plate, 240 mm deep, all connectors on...
View Articlepcbprt - Experiments in inkjet PCB printing
For the last few years hobbyists worldwide have been experimenting with inkjet PCB printing, i.e. manufacturing electronic circuit boards with inkjet printers. This is a report on my experience with...
View ArticleWXHMD - A Wireless Head-Mounted Display with embedded Linux
WXHMD is a Gumstix Overo Fire computer-on-module driving a Vuzix VR920 head-mounted display: Stereoscopic 640x480, audio in/out, 3D tilt sensor, 3D magnetic compass, TI OMAP3530 @ 600 MHz, Linux,...
View Articlelinmctool - Linux motion-sensing controller tool
linmctool provides minimal support for popular Bluetooth motion-sensing game controllers on Linux: PlayStation Motion Controller (PS Move), Sixaxis, DualShock3, Wii Remote (Wiimote).
View ArticleHomodyne measurement of Earth's rotation with a motion-sensing videogame...
Got a PlayStation Move and an old vinyl turntable ? You can try to detect Earth's rotation, find geographic north, and determine your latitude.
View ArticleLoad-testing generators with Gray codes
Digital circuit theory meets gasoline engines as we design a monotonically-adjustable, low-component-count dummy load suitable for testing electric generators in the kilowatt range.
View ArticleInteresting factoids in science and technology
A collection of little-known, counter-intuitive or otherwise enlightening facts in various fields of science and technology.
View ArticleA taxonomy of Heartbleed attacks
One week after the disclosure of the Heartbleed vulnerability, security experts are still discovering new ways it could affect online security. This document attempts to classify attack patterns and...
View ArticleThe science of garden swimming pools
How an engineer looks at kiddie pools: tensile strength of curved walls, thermal conductivity, evaporative cooling, blackbody radiation, Sun ephemerides, and water sanitation techniques.
View ArticleBitcoin's centralized endgame, and how to avoid it
We review 18 common misconceptions about the Bitcoin crypto-currency system and show how the reality helps predict its endgame: centralized mining, then centralized governance. We suggest that...
View Articlebrickhid - Direct connection between Bluetooth gamepads and LEGO Mindstorms...
We show how to interface LEGO Mindstorms EV3 directly with off-the-shelf Bluetooth gamepads and joysticks such as the PS3 SIXAXIS and DualShock 3 controllers.
View ArticleSeeing the world through a depth-sensing camera
In this project we attach a depth-sensing camera to a head-mounted stereoscopic display (think: Kinect + Google Cardboard). The resulting portable device allows users to see their surroundings in...
View ArticleFirst-person view and remote control with LEGO Mindstorms EV3
We add FPV and RC functionality to a LEGO Mindstorms EV3 vehicle with a PlayStation gamepad, USB webcams, a smartphone-based stereoscopic head-mounted display, and the alternative operating system...
View ArticleA better audio jack console cable for Google Nexus devices
Many Google Nexus smartphones and tablets have a serial console which can be accessed through the headset socket. This is an invaluable tool for software development. Unfortunately there are no...
View ArticleToward mobile Linux devices with auditable security
This web page documents my attempts to assemble Linux smartphones and tablets with as few non-mainstream components, binary blobs and potential backdoors as possible. Currently the best candidate is a...
View ArticleSDR reception of Digital Amateur TV from the ISS
How to receive DVB-S digital video transmissions from the International Space Station with a bit of hardware and a lot of software.
View Articleleandvb: A lightweight software DVB-S demodulator
leandvb is a lightweight implementation of portions of the DVB-S standard in plain C++. It is developed primarily for receiving Digital Amateur TV, including HamTV from the International Space Station.
View ArticleHAMPADS: HAM-Portable Affordable Dish for Satellites
A shoulder-mounted dish, receiver and tracking system for amateur radio communications, originally designed for receiving HamTV digital video transmissions from the International Space Station.
View ArticleToward thermoelectric production of dry ice ?
In this project I try to make dry ice by cooling carbon dioxide to -80°C with Peltier modules.
View ArticleDemodulating the Outernet signal with leandvb
In this article I explain how to demodulate Outernet L-band satellite broadcasts with leandvb . The techniques developed for this project may also be relevant to other low-cost narrowband applications...
View ArticleLeanTRX: A web interface for embedded SDR platforms
LeanTRX adds a web interface to the LeanSDR toolkit. Its main purpose is to turn embedded SDR platforms into user-friendly, multi-mode RF modems which can be controlled with any web browser. Potential...
View ArticleKu-band LNB line-up
In this article I document the internal construction of several off-the-shelf Ku-band low-noise-block downconverters (LNB/LNBF) from the perspective of amateur radio applications.
View ArticleSoftware-defined demodulation of Digital Amateur TV from QO-100
Since 2019-02-14, licensed amateur radio operators can videoconference via QO-100, the first amateur transponder in geostationary orbit. In this article I explain how to receive some downlink signals...
View ArticleTesting the Othernet "Bullseye BE01" LNB
The Othernet Bullseye BE01 Ku-band Low-Noise Block-downconverter features a tunable 2 ppm TCXO, a 25 MHz reference output, and extended coverage for QO-100 reception. In this article I discuss its...
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